Looper mechanism i or   sewing machines



April 20 1926.

J. P. WEIS LOOPER MECHANISM FOR SEWING MACHINES File Oc 9. 1923 6Sheets-Sheet 1 I NV EN TOR. L/bH/YR I'VE/s.

April 20, 1926. 1,581,497

J. P. WEIS LOOIER MECHANISM FOR SEWING MACHINES Filed Oct. 9, 1923 6Sheets-Sheet 2 I N VEN TOR.

April 20', 1926. 1,581,497

J.. P. WEIS LOOPER MECHANISM FOR SEWING MACHINES Filed 9' 1925 6Sheets-Sheet 5 ./I-NVENTOR.

1 April 20 1926.

J. P. WEIS LOOPER MECHANISM FOR SEWING MACHINES G Sheets-Sheet 5 Filed001;. 9, 1923 Mb 2 J mum April 20,1926; 1,581,497

- J. P. WEIS 'LCOPER MECHANISM FOR SEWING MACHINES Filed Oct. 9. 1923 6s t -Shae} 6 I N VEN TOR.

JoH/VB M/S.

in dotted lines and the transmitter shown in operating position underthe machine, but detached from the work table to more clearly illustratethe relation of the transmitter with the sewing machine; Fig. 2 is afront perspective view of the sewing machine, transmitter and treadleconnected for operating the same; Fig. 3 is a perspective view of theend cap for covering the looper and thread controlling mechanisms; Fig,4 is an end View of the needle bar operating mechanism, portions of theneedle bar bushings, oil cup and needle bar being broke away to moreclearly show the construction, and a portion of the arm and crank shaftshown in broken lines; Fig. 5 is a back elevation of the machine,illustrating the connections for the needle drive and: a portion of thelooper and feed actuating mechanisms; Fig. 6 is a side elevation of thefeeding mechanism, parts being broken away to clearly show theassemblage; the overhanging portion of the arm and the machine framebeing indicated in broken lines; Fig. 7 is a top plan view of thecylindrical portion of the machine illustrating the looper mechanism;Fig. 8 is a side elevation of the mechanism shown in Fig. 7, theoverhanging arm of the machine being indicated in broken lines; Fig. 9is an end elevation of the cylinder, illustrating the mount ing of theloopers and needle guards; Fig. 10 is a perspective view of the circularholder for the loopers; Fig. 11 is a perspective view of the arm whichsupports the circular holder for the loopers; Fig. 12 is a perspectiveview of a looper; Fig. 13 is a perspective view of the needle guard andholder; Fig. 14 is a detail view partly in section, illustrating alooper; ,Fig. 15 is a detail-plan view of a form of looper; Fi 16 is adetail view of the lower end of the looper actuating connection, aportion being broken away to clearly show the assemblage of the parts;Fig. 17 is an end elevation of the cylinder and looper actuating means,partly in section taken 011 lines 17 17 of Fig. 7; Fig. 18 illustratesdiagrammatically the movement of the looper actuating means; Fig. 19illustrates diagrammatically the elliptical path of movement of theloopers; Fig. 20 is a diagrammatic view illustrating the manner in whichadjustment of the looper mechanism may be made in order to change theoscillation of the loopcrs from front to rear of the needles, forcooperation of the loopers with needles of different sizes; Fig. 21 isan end view of the cylinder showing the-looper thread controlling means,with the looper in its extreme forward position; Fig. 22 is a view ofthe part shown in Fig. 21 with the looper in position for the needle toenter between it and a strand of the looper thread, also showing thethread clamped by the thread controlling mechanism in full and dottedline position, the full lines representing the thread being clampedwhile the needle is moving downward and the looper is moving backward,and the dotted line position representing the thread clamp open for freemovement of the loop-er thread While the looper is moving in theopposite direction; Fig. 23 is a view similar to Figs. 21 and 22, butshowing the looper in its rearmost position, where it shifts from frontto rear of the needles, and at which time the thread clamp is open asthe needle starts to rise and the looper moves toward it to enter theneedle loop; F ig. 24 is a perspective view of a group of parts of thelooper thread controlling means; Fig. 25 is a fragmentary perspectiveview of the end of the cylinder, showing a portion of the throat plate,looper thread clamping means, and the looper thread guide tubes whichconduct the thread from the rear of the machine to the threadcontrolling mechanism; Fig. 26 is a perspective view of the looperthreadtake-up or controller; and Fig. 27 is a detail elevation view of thelooper thread guide tubes, thread clamp, and a portion of a rock leverwith guide eyes for conducting the thread to the loopers.

Before explaining in detail the present improvement and mode ofoperation thereof, I desire to have it understood that the invention isnot limited to the details of construction and arrangement of partswhich are illustrated in the accompanying drawings, since the inventionis capable of other embodiments, and that the phraseology which I employis for the purpose of description and not of limitation.

Referring to the drawings, it will be seen that the present machine ismounted upon a suitable table 1 and comprises a machine frame havingflanges 2 and 3 for supporting and securing the machine to the table.The main portion of the frame is preferably of hollow rectangularconstruction, closed at the bottom, and having a front wall 4t and arear wall 5 provided. with an opening 6 adapted to be closed by means ofa cover plate 7 attached thereto in any suitable manner. The machineframe with its enclosing walls forms of itself an oil reser-VOl1,-Zl.1'l(l pump mechanism (not shown) is located therein forlubricating the various bearings of the. machine. The machine frameforms an oil tight chamber against the escape of oil to the outside.This cover plate is provided with a hollow? projecting portion 8 withinwhich operates a stop lever for the stopping and starting mechanism ofthe machine. The front wall l of the frame is provided with a boss 11bored to receiw e a cylinder 12. The side wall 13 of the frame isprovided with a boss 14L for receiving one of the crank shaft bushings15,

the opposite sidewall having secured thereto the sewing machine.Suitable clutch mecha suitable belt guard 22 which covers'the drivingbelt 23. The frame is provided with inwardly projectingb'osses 26 and 29bored to receive bushings for supportingthe crank shaft of the machine.Projecting from the front wall 4 is an overhanging arm 32 terminating ina bearing 33. j

The overhanging arm 32 is provided with suitable bearings 37 and 38 fora needle operating rock shaft 39. Secured to the forward end of the rockshaft 39 by screws 10 is a needle bar operating arm 41. The end of theshaft 39 is tapped to receive a screw 42 and a thrust washer 43 therebyto prevent end movement of the arm 41 on the shaft 39. At the outerendof the arm ll bymeans of a joint pin 44' is secured a link t5, thebottom end thereof being connected by means of a joint pin 6L6 to an endpiece a'i'tapped into the needle bar 48 and clamped with a lock nut 49.The needle bar is hollow and the lower end is tapped to receive theneedle holder 50 which carries the needles 51. The needle bar isprovided with two openings 52, the upper one being an'inlet and thelower one-an outlet for oil for the purpose of internally oiling theupper and lower needle bar bushings, 53 and 54C. v

Secured'to the top of theupper bushing is an oil cup 55 provided with afelt oiler, carrying sufficient lubricant for the needle bar, butpreventing the oil from dripping and soiling the goods. Anintermediate'felt oiler 56 ispr'ovi'ded between the two bushings. Thesefelt oilers wipe the needle bar in its reciprocating movement, keepingit clean and properly lubricated.

To the rearend of the rock shaft 39, adja cent to the bearing 37 issecured a crank arm 57 and ball stud 58, to which is connected the upperend of a ball connection 59. The lowerfend 60 also has a ball sockettofit over the ball 61 of the crank shaft.

A presser bar 183 reciprocates vertically in a bushing 187 carried bythe bearing 33, and a presser foot 188 is secured to the lower end ofthe \presser bar. Above this bearing is a rectangularopening 3-l throughwhich the presser foot lifting member 180 operates.

hlounted in end" bearings 15 and99 of the frame, and in suitablebearings inbosses 26 and 29 is a transversely extending crank shaft 62.63 having a clutch wheel 93 provided with a suitable belt groove overwhich passes belt 23 of the transmitter.

The power transmitter comprises in general a main bracket'1 l3 securedto the bottom of the table in any suitable manner, the bracket having anarm bored to receive a shaft 144. Upon this shaft is mounted a conepulley 1&5 over which operates a belt 146 for transmitting power fromany s fi itable line shaft to the pulley. The belt 23 is driven by apulley-149 foroperating anism for the pulleys 145 and 149 is providedwhich is controlled by meansiof a rod156 connected to floor treadle 159.A further detailed description of the power transmitter mechanism is notdeemed necessary herein since the same is fully described in mycopending application.

Referring to lfiig. G, a four-motion feedi.) ing mechanism coactiug withthe presser foot. is provided for feeding the work through the machine.This mechanism comprises a feed dog 208, which may be of any preferredform to suit the character of work. $9 This feed-dog is adjustably anddetachably mounted upon a feed bar 213, which is rock ably supported inthe cylinder 12 by a swinging yoke link 220 embracing the bar;Four-motion movementsare transmitted to the feed bar by the ball crank69 of the crank shaft operating in the bearing 230 of the feed lever231. The rear end of the feed bar 213 is connected to the feed lever 231by means of a oint pin 233. Mechanism is provided for adjusting andregulating the length of stitch or the throw of the feeodog, preferablyby means of self-locking adjusting mechanism. A detailed description ofthis mechanism is not deemed 95 necessary herein, the same being fullydescribed in my co-pending divisional appli cation Serial No. 667,453filed October 9, 1923. i

It will be noted that the feed: bar is upwardly inclined at its rear endand is trough shaped from end to end, whereby anopen flow of lubricantis conducted thru the cyl inderto the bearings and since the cylinder issupported in inclined position the lubricant will flow back thru thebottom of the cylinder into the machine frame. The motion of the feedbar throws the oil to the adjacent operating or bearing parts. By

means ofthe threaded tubes and. the location of the thread handlingmechanism, the

with a tapered shank 273 adjustably secured in the wall 13 of themachine frame by two screws 27-1. lly loosening these two screws, andinserting a screw driver in the slot .274, the yoke bracket 272 may beturned so as-to tilt the position of the rock shaft 2. O'fronrthe fullline horizontal position indicated in Fig. 20 to the dotted lineposition, such line bearing the numeral 270 corresponding to the axis ofthe shaft 270. iVhen adjusted to the full line position the swingingmovement of the ball 268 is perpendicular to the shaft 270, asrepresented by the full line 268 in the diagram, Fig. 20, whereas if theshaft 270 is adjusted angularly as for instance to the dotted lineposition 270, the ball 268 will swing at an angle from theperpendicular, as represented by the dotted lines 268 The tapered shankof the yoke 278, is represented by the circle 273 in the diagram. Thearm 269 is clamped to the shaft 270 by a screw 275, and is held againstsidewise movement by the bearings 271, one on each side of the arm.

The ball socket 267 comprises a cap forming the lower portion of thesocket 276 secured to the connection 266 by screws 27?. This cap isbifurcated to receive a block 278 pivotally supported by a pair ofconical screws 279. Clamp screws 280 clamp the conical screws inadjusted position so that the block 278 may rock onthe screws withoutside shake. This block is bored at right angles to the conical socketsfor the screws to receive a looper shaft rocking pin 281 securelyclamped to the rear end of the looper shaft 282 as by a clamp screw 283.The pin 281 is provided at one end with a head 284i to limit the endwiseadjustment of the pin in one direction and to prevent the pin strikingthe inclined surface 285 of the cap 276. In the present instance thelooper shaft is made in two parts, the rear end 282 being of largerdiameter than the forward extension 292, the parts? being connected inany suitable manner.

The rear shaft portion 282 operates in a. bearing 286 secured in thecylinder 12 by screws 287, the bearing having an opening 288 at the topto provide working space for the feed bar and having two saw cuts 289,in the front and rear wall diametrically opposite the hole in which theshaft 282 operates. Clamping screws? 290 are provided to adjust the sawcuts for adjusting the bearing 286 to fit the shaf 282 thereby taking upwear. The rear wall of the bearing 286 is recessed at 291 to provideclearance for the bottom cap 276 of the ball socket.

Fig. 18 illustrates diagrammatically the operation of the looperoperating means above described. The circle A indicates the motion ofthe ball crank 67, indicated by B. The line C represents the connection266, and the ball 268 is represented by D, and the connection betweenthe block 278 and the pin 281 is indicated by E. The direction ofrotation of the crank shaft is indicated by the arrow in Fig. 18.

Referring to the diagrams of Fig. 18, the action of the looper operatingmeans is follows: As the shaft rotates from F to G the bottom end of theconnection E shifts from the position H in the diagram to the positionI, bringing the connection C to the perpendicular position, and the ballD upon which the lever C is fulcrumed, from the central position J tothe lowest posit-ion K. Further rotation of the shaft brings the crank15 from the position (i to the position L, and the connection it to thepoint lil. Further rotation of the shaft brings the crank from theposition L to the highest position N and the connection E to theposition 0, and the ball D to the position P.

l urther rotation of the shaft brings the crank B from the position N tothe starting position l3, and the ball D to the position J, and theconnection E to the position H compicting a cycle of movement whichgives to the looper the elliptical movement as indicated by the lines Qof the diagram.

From the foregoing it will be seen that the ball 268 carried by the arm269 secured to the rock shaft 270 forms afulcrum for the leverconnection 266 which is reciprocated by the ball crank 67, the center ofthe fulcrum formed by the ball 268 being relatively close to theconnection made between the looper shaft pin 281 and the block 278. Thevibratory movement of the loopers, indicated in the diagram of Fig. 18at H and M represents the movements of the looper from front to rear ofthe needle, while the movement of the looper into and out of the needleloops is indicated in the diagram at I and O. The-path of movement ofthe looper may be varied to accommodate varying needle sizes rthicknesses as shown by the diagrams of Figs. 19 and 20, one having aperpendicular line passing through the major axis of the ellipticalpath, and the other having an inclined line passing through the majoraxis of the elliptical path. The perpendicular position of theelliptical path represents the movement given to the loopers whencoacting with a relatively thin needle, while the angular position ofthe elliptical path represents the movement given to the loopers whenoperating with a. thick needle. It will be seen that the distance from Rto S is greater than the distance from T to U in Fig. 19, which distanceis increased by reason of the shaft 270 being adjusted to the angulardotted line position 270 shown in Fig. 20, whereby the ball 268 carriedby the arm 269 swings on the angular line 268 thus shifting theelliptical path from the perpendicular to the angular position andutilizing a portion of the vertical reciprocation for the horizontalvibration of the looper.

Thus where a relatively thin small gauge needle is used the movement ofthe looper from front to rear thereof is shown from TV to X in Fig. 19,while if a larger needle is used the required angular adjustment of theelliptical path of movement of the looper will increasethe vibratorymovement of the looper asfroin Yto Z, 19, so as to enable the same tocoaet withthe thicker needle at the front and rear thereof.

he forward end of the looper shaft 292 is supported in the bearing 248secured in the cylinder12 by the screws 293. Secured to the free end ofthe shaft 292 by the clamp screw 294 is a crank arm 295 to which isattached by a screw 297 for vertical adjust ment a circular holdercarrier 2% for the looper-s. The clamp screw 294 in the aperture 299,Fig. 11, adjustably clamps the arm on the looper shaft, the arm'having asaw cut 300 permitting this adjustment. The clamp screw 297 of thecircular holder for the loopers is screwed into the aperture 301 of thesleeve, and the side walls of the recess 302. straddle the side walls303 of the lug 304 of the supporting arm for the looper car-' rier,permitting vertical adjustment of the carrier and loopers. This circularor rlng shaped carrier or holder iscut away to form end portions 305 and306 to give working space for the needlesand loopers, and the hole ,307also provides clearance for the needles. Adjacentto the end 305 are twotapped holes '308for the reception of screws 309 and 310, one adjustablysecuring a thread'carryinglooper 311, and the other adjustahly securinga like thread carrying looper 312 to the front and rear walls of thering shaped looper carrier In the description of the stitchln'gmechanism the term forward is herein used to refer to the direction inwhich the looper points, the. term backward to the oppos te direction ofthe looper movement. With reference to the terms front and'rear of theneedles, front is intended to 111621118 the side facing the operator,while rear refers to the reverse side of the needle. I The loopers 311and 312 are identical and comprise a blade 313 terminating in apoint314, and an undercut thread groove. 315 extending from the front eye 316to the rear eye 317. p

The groove 315 of the looper, as shown in Fig. 14, is constructed withan overlapping wall 315, which acts to retain the thread in the grooveand prevents it from slipping out of the groove and extending 1p astraight line between eyes 316 and 311. It has been found in practicethat where a groove is provided on the fiat face or side of a circularlooper, that the thread has a tendency to extend aerossthe arc of thelooper thereby interfering with the needle-loops. The undercut groove315 however, prevents the looper thread from getting out of the groove,thereby preventing the shipping of the stitches, the breaking of theneedle and looper thread, and enabling the machine to produce moreuniform stitching. As shown in Fig. 15, the looper blade may be offsetat 316 for the purpose of creating a back drag on the needle loops. Alooper of this construction is often used in a twin needle ma chine formaking ornamentalcovering stitch. The shank is segmentally slotted at318 for the screws 309 and 310, and the bottom por justment, whereby asingle style or sizeof 4 looper may be used with different needlegauges, or for different stitch formation, thus avoiding the necessityof providing separate loopers of dilferent sizes or shapes foreverydifferent spacing. of needles or needle gauge or character of work.

"The holes 322 adjacent t'o the end 306 of the ring shaped or curvedholder receive screws 323 and 324 for adjustably attaching theneedleguard holders 325 and 326, each holder having a bent wire 327,adjustably secured therein, each wire having a tapered point 327 andbeing so shaped as to act as a needle guard to control the path and toposition them properly with respect to the point of the looper, thusovercoming the skipping of stitches and breaking of needles. I

The holders comprise a head 328 within which the wires 327 are secured,and a flattenedshank 329 slotted at 330 for the reception of screw 323or 324 for securely fastening the needle guide holders to thecircularholder 296. The circular portions 331 of the shanks of theholders fit snugly against the flanges of the carrier at 332 and 333 toprevent the guards 327 from shifting relatively to the carrier. Thusitwill be seen from this contruction thatthe needle I guards may beadjusted as desired for all needle guages and for allsizes of needles,the needle guards and loopers being adjustable one relatively to theother or bothrelatively to each other.

Coacting with the. stitching and feeding mechanism is a throat plate334, see Fig. 25, secured to the forward bearing 248 by screws 335,Fig. 1. The throat plate is provided with the usual feed slots 337through which operate the serrated surfaces 336 of the feed dog 208, thethroat plate also being provided with the usual needle holes (not shown)through which the needles operate. The throat plate is of segmentalconstruction forming with the cylinder 12 a complete circle whenattached thereto, the cylinder being cut away on the lines 338-338 toreceive thethroat plate. A projecting tongue needles in case theydefiect'out of thevertical 338 of the throat plate cooperates with agroove formed in the cylinder, Fig. 8, so that the projecting portion339 overlaps the tongue 338, thereby securely holding the rear end ofthe plate from tipping or moving when the pressure of the foot isbrought to bear upon the outer overhanging end of the throat plate.

Referring particularly to Figs. 1, 2 and 3, the forwardly extending end340 of the throat plate is provided with beveled or inclined edges 3&1,and an end cap or cover 343 fits thereover, the dove-tailed grooves 342of the cap cooperating with the inclined portions 341 and hence the samemay be shifted on and off the forward end of the throat plate. The sidewalls of the cap 3 A are partially slotted to make them flexible so thatthe cap will yield and properly fit over the beveled or inclined edgesof the throat plate. The end cap is hollow to provide free working spacefor the loopers and other parts adjacent thereto. In order to secure thecap 3-13 to the cyl iuer and 'sar'in is suitabl secured inside of theend cap as by a screw 3e3 Fig. 3.

As illustrated in Figs. 1 and 25, the cylinder 12 may be provided at itsforward end with a projecting portion 345 extending outwardly tocorrespond in length approximately with the overhanging portion 3&0 ofthe throat plate, theextension 345 being provided with an end wall3et6to prevent lubricant from escaping, the bearing 2&7 having a hole482 to allow the lubricant to flowback into the cylinder in rear of thehearing. The curved side 'alls 3&7 of this extension are adapted to liein juxtaposition tothe curved walls of the cap 343 thereby forming asupport upon which the bottom edge of the end cap res s.

It will be seen that by reason of the fact that the feeding and loopermechanisms are arranged and supported within the cylinder 12-, the samehaving the enlarged opening 12 covered "by the throat plate extending aconsiderable distance in the rear of the needles I may do away with theuse of a cover plate, and as a result of this construction greaterrigidity of the parts is se cured, as well as free access to theinterior of the cylinder, thus eliminating loose parts with the addedadvantage of using a cylinder of equal diameter throughout its length.

The cylinder is preferably constructed of steel tubing of smalldiameter. Such tubular work may be handled with greater facility thanthe usual casting which is tapered from the free end toward the machineframe, and at the same time giving the increased advantage of greaterstrength and rigidity. In the present machine the cylinder is detachablysecured in the boss ll by spot clamping serews3-t9, permitting thecylinder to be removed and replaced by disconnecting the operating meansfor the looper and feed within the rear trunk of the machine. To preventthe leakage of oil between the cylinder 12 and the boss 11 a wick insert350 of suitable material is provided which fits into a groove of thecylinder 12 to form a leak-proof joint between the parts.

Referring to Figs. 2, 21, 22, 23, 24-, E25, 26 and 27, improved meansfor controlling the looper threads is provided. Secured to the endbearing 2&3 is a two-arm rock lever 351, supported by the shoulder screwscrew threaded into the end bearing. An arm of the rock lever carries atits free end a flared portion 354, projecting from one side thereof andhaving a tapered inclined or cam surface 355 terminating in a flatsurface 356, Fig. 24. The upper edge 357 of the arm 353 is adapted tocoaet with the rounded end 353 of the cam 359 adjustably secured to thelooper shaft 292 adjacent to the outside face of the end bearing 248 byset screws passing through the tapped holes The cam rocks the lever onthe screw as required to control the looper thread or threads, andswings the lever downwardly away from the looper shaft 292. On thereturn movement, in order to keep the lever in contact with the eoactingsurface of the cam a flat spring 361, having its free end restingagainst the upper portion 362 of an arm 363 of the rock lever 351 isprovided.- This spring is clamped by a screw 364; into a T-slot of theend bearing 2-l3, as shown in Fig. 25. The spring 361 has a plate 3%attached to it to provide a better clamping surface for the'screw At thetop of the arm mm 1 provide, adjacent to the portion 362 co-acting withthe spring, a wa l having an aperture 363 to receive the body 36$) ofthe screw 370, while an opposed wall 371 has an alined aperture screwthreaded to receive the thr aded end 372 of the screw 370. The walls 367and 371 are spaced at 373 to receive a rocking plate 371; having anaperture 375 for the screw 370 which rock ably supports the plate. Thepurpo:-.'e of this rocking plate 37a is to act upon the looper threadsand clamp them against the surface 376 of the inner wall of the cylinder12. The wall 371 is cut out to form two lugs 377 and a space 378therebetween for the passage of thread, these lugs or projections 377acting as separators forthe looper threads to prevent them from tanghngand to so control and guide the threads one above and the other belowthe center line in the. right angled wall 383 leading tot-he I top edge382 permits the threadingotv the eyelet in the wall 380. The wall 383hasa I second slot384 leading from the thread hole 385 in the end wall386, and also emerging at the top 382 to permit the thread to beinserted in the hole 385.

Between the walls 380 and 386 operates the looper thread take-up orcontroller, comprising a circular shank at 387 provided with anelongated slot 388, 'throughwhich' passes a clamp screw 389, Fig. 1,'torsecuring. it to the rounded surface 390 of the arm 295, Fig. 11,carrying the loopers, the screw 389 fitting into the tapped hole 391.The thread controller is curved at 392,reversely t0 the curve at 387-and is bent in a haltloop at 393, and forms witha curved portion 394, aneck 396,7and a curved shoulder 395, terminating in a o'mt 397. The controller is so shaped as to properly actupon the looper thread or-threadsfor controlling the same during the stitch formation;

From the foregoingflit will be seen that I have provided a very simple,compact, and

reliable means forcontrolling the looper threads, QCCQSSllOlY located inand covered by the end cap of the machine, and comprising athreadclamp'or nipper 374: and a thread take-up or controller 387to'give, and take-up thread at the desired intervals of each stitchforming cycle. The improved location of the parts otl'ers advantages inthreading and'adjustment, one of the lint portant advantages residing inthe fact that when the 'looper' thread breaks, the broken end of thethread usually lies close to the looper and hence rethreading in'thepresent machine is easy due to the convenient location of the parts.Heretotore thread controlling mechanisms have been located in thecylinder oratthe rear of the machine, thereby rendering the parts veryinaccessible. Usually action on the thread of the th read-controllingmechanism causes breakage of the thread where weak spots or knots occurin the thread, and when so located, loss of time occurred in therethrcading. I away with in they present improvement on account of thethread-controller being located at the stitching position. By reason ofthis construction itis possible to timethe action of the cam 359 withrespect to the I movement of the loopers so thatits end 358 needleloops,

All such loss of time is done will coact with the arm 353 of the lever351 to permit thenipper or clamp 374: to

hold the looper threads tightly between the surfaces 39 and 376 whilethe loopcr is moving rearwardly outoi the needle loops and so hold themuntil the point of the needle has passed between the looper and a strandof the! looper thread. That is to say, the clamp is closed upon eachlooper thread 399' while the thread remains in the neck'396 of'thecontroller during the backward movement of the loopers, and thatportionoi each looper thread which extends from the thread clamp throughthe eye of each looper and up to the preceding stitch is drawn backwardfree from slack, as shown at 400 in Fig. 22. Immediately upon the pointof the needle-reaching the position in Fig. 22 the end 358 of the camcontacts with the inclined surface 355 of the lever 351 and swings itdownwardly to the dotted line position :01, Fig. 22, thereby releasingthe grip of the thread clamp upon the looper thread. directionot thearrow uponthe flat portion 000, and thereupon moves backward while thelooper is passing from the front to the rear of the needle, thus causingthe surface 358 ot'thecam to travel directly over the surface 357 of thearm 353 to hold it down against the actionof the spring .361 until thecamreaches the position in Fig. 21, representing the extreme forwardmovementnof the looper. During this forward movement the thread clamp isheld open or released to permit the free movement of the loope r threadfor theztormationoi the next stitches.

Simultane nsly as the loopersreach the end of this forward movement asin Fig. 21, the loopers are shifted from the rear to the front sideoithe needle, thus shifting the end 358 otthe cam oil of the surface 357at which time the spring 351 swings the lever 351 upwardly and closesthe thread clamp, holding it closed during the backwardmov ment of thelooper out of the and until the needle point has passed down'between theback of the looper and astrand of the looper thread.

The action of the thread controller in conjunction with the threadclampis such as to act upon theilooper threads to take up the slackduring thebackward movement of the loopers, and simultaneously as the thread clampopensthe loops 4030f the backward movement oi the loopers the loops Iare drawnup into the bend 393 of the thread eontroller as showninFig.23. The

loopcr threads remain in such position dnring the forward movement ofthe loopers, the same drawing theneeded thread from the supply throughthe thread eye 385,'and

holding the thread so that it will positively draw through the neck 396.As the loopers reach their extreme forward position, as indicated inFig. 21, and simultaneously as they shift from rear to frontof theneedles, for the return movement, the thread clamp 3A, as hereinbeforedescribed closes upon the threads, and inasmuch as the strands of thelooper threads 399, extending from the hole in the wall 380 to the holein the wall 386, lie in the neck 3%, the same are carried downward in aninwardly curving path to the position indicated at L00, whereupon thenip-per or thread clamp 1s released or opens and the threads are castoff, thereby giving the necessary slack thread for the tying of thestitches.

Thusit will be seen that the arrangement of the looper threadcontrolling parts is such as to positively act upon the looper threadsto control the slack, and after the slack has been controlled, thecontroller 38'? reaches a position where the thread is automaticallycast out of the neck 396, due to the angular relation between the threadguides and the position the neck 396 assumes after the needle hasentered, as in 22, between the looper and looper thread during thestitch-forming cycle. h

Referring to Figs. 3, 5, 17, and 24, in order to conduct the looperthreads 399 from the supply to the thread controlling mechanism, twothread tubes act are provided which extend from the rear through themachine housing, and through the cylinder 12 where the forward ends e06terminate close to the thread controlling means. This arrangement offersthe advantage of conducting each thread separately from a position closeto the supply, through the interior of the machine, and keeps themontirely protected from the operating mechanism and lubricant, and alsoprevents any lint carried through by the thread from accumulating in themachine. The threads are thus separately encased or housed throughoutsubstantially the length of their travel. Two apertures are provided inthe lower portion of the cover plate 7 through which project the ends(Fig. 5) ofv the thread tubes 40a. The bearing 286 is slotted at 4-05(Fig. 17) to permit the tubesto pass therethrough one above the other.

The end bearing 21-8 is also cut out as shown in Fig. 25 to permit thethread tubes 4.041; to pass between the inside wall of the cylinder 12and the end bearing. The outlet ends of the tube 406 are locatedadjacent to the elongated slot 407 provided in the wall of the cylinder12 to permit threading wires to be inserted in the tubes 410 i fordrawing the end of the thread through. An angular saw-cut 408 extendingfrom the elongated slot to the edge of the cylinder permits the threadto be placed in between the wall 876 of the cylinder and the surface 398of the controller clamp 37st.

It is to be understood that by describing in detail herein anyparticular form, structure or arrangement, it is not intended to limitthe invention beyond the terms of the several claims or the requirementsof the prior art.

Having thus explained the nature of my said invention and described away of constructing and using the same, although without attempting toset forth all of the forms in which it may be made, or all of the modesof its use, I claim:

1. In a sewing machine, the combination of a looper shaft, a loopercarried by said shaft, means for moving the looper in an elliptical pathduring its curvilinear movement, and means for imparting to the looper adifferent elliptical path of movement at an angle to the other to causethe looper to move a greater distance forwardly and a greater distancerearwardly at the opposite ends of its transverse movement into and outof the needle loops.

2. In a sewing machine, the combination of a needle, means for impartingto the looper an elliptical path of movement relatively to the needle,and means cooperating with said means and adjustable to impart to saidlooper a different elliptical path of movement in which the looper isthereby caused to move a greater distance rearwardly relatively to theneedle at one end of its loop taking throw and a greater distanceforwardly relatively to the needle at the opposite end of said throw.

3. In a sewing machine, the con'ibination of a machine frame comprisingan oil chamber having enclosing side walls, a needle, a looper, meansfor imparting to said looper an elliptical path of movement relativelyto the needle, and means coopcrating with said means and accessible foradjustment from the outside of said machine frame for imparting to saidlooper a different elliptical path of movement in which the looper isthereby caused to move a greater distance rearwardly of the needle atone end of its loop-taking throw and a greater distance forwardly of theneedle at the opposite end of said throw.

4. In a sewing machine, the combination of a needle, a looper, means formoving the looper in an elliptical path during its curvilinear movement,and means cooperating with said means for n'ioving the looper in adifferent elliptical path at an angle to the other in which the looperis thereby caused to move a greater distance rear- Wardly relatively tothe needle at one end of its loop-taking throw and a greater dis* tanceforwardly relatively to the needle at the opposite end of said throw.

5. In a sewing machine, the combination elliptical path during. itscurvilinear movement, and means for imparting to the looper a differentelliptical path of movement at an angle to the other while maintainingthe centers of said elliptical/paths approximately the same, said meanscomprising a pitman, and an adjustable shaft having a swinging fulcrumpivoted thereto and co-' operating with said p tman.

6. In a sewing machine, the combination of a needle, a-looper,meansformoving the.

looper in an elliptical path during its curv ilinear movement, and meanscooperating with said means for moving the looper in a differentelliptical path at an angle tothe other in which the looper istherebycaused to movea greater distance'rearwardly relatively to theneedle atoneend of its looptaking throw and a greater distance for wardlyrelatively totheneedle atthe opposite end of said throw, saidmeanscompris ing a pitman' and an adjustable shaft having a swinging fulcrumpivoted thereto and cooperating'with said pitman. 5

7.- Ina sewing machine, th of alooper shaft, a looper. atone endthereof, a crank pin secured to the-opposite endof said shaft, a driveshaft, apitman operated thereby and connected to saidcrank pin forrocking said looper shaft, a shaft, a swinging fulcrum pivoted theretoand fulcrumed onsaidpitman, and means-for angularly adjusting said lastnamed shaft.

8. In a sewing machine, the combination of a hollow machine framecomprising an oil reservoir having walls enclosing the same against theescape ofoil'to the outside, a drive shaft, a looper shaft operated fromsaid shaft, means located in'said reservoir for adjusting the path ofmovementof the looper, and means'extending through one of said walls andhavingan oil tight joint. therewith for operating said adjusting outside"of the machine means from the I frame. a

9. In a sewing machine,thecombmation of needle mechanism,a looper, andmeans for imparting to said looper a four motion path of movement-andincluding means operative to vary said path ofmovement of the looper tomove the'looper a'greater distance forwardly of the needle at one end ofits throw into and out of the needle loops and a greater distancerearwardly of the needle at the opposite end ofsuch throw.

10. In a'sewing machine, the combination of a hollow machine frameenclosed on all sides, needle mechanism, a drive shaft, a

looper shaft, a looper connected to said shaft, a crank lever withinsaid frame and connect ing said shafts a fulcrum shaft, fulcrum meanspivoted thereto and cooperating with said lever, .and means normallyaccessible e combination.

. 11., The combination'of-needle mechanism,

a drive shaft, a looper shaft, a looper-carried by'said shaft, a leverconnecting said drive shaft andlooper shaft, a swinging member having apivotal axis and forming afulcrum for said lever, and means forangularly ad.- j usting the pivotal axis of said memben 12. Thecombination of needle mechanism, a driveshaft, a looper shaft, alooper-controlled by said shaft, a reciprocating member connecting saiddrive. shaft and looper shaft a swinging member having a pivotal axisand forming a fulcrum for said reciprocating member, said swingingmember normally extending at right angles to said looper shaft, and.means for adjusting the pivotalaxis thereof. v

13,111 a sewing machine, the combination of needle mechanism, a driveshaft, a looper shaft operated therefrom a looper carried by said loopershaft, means for moving said looper in various 'angularly related paths,

said means comprising a reciprocating lever connectedto said driveshaft, an angularly adjustable'shaft, and afulcrum connection betweensaid leverand adjustable shaft.

14:. In a sewing machine, the combination of needle mechanism, a driveshaft, a looper shaft operated therefrom, a looper carried by saidlooper shaft, means for imparting to said looper various ellipticalpaths of movement, said means comprising a reciprocatinglever connectedto said drive shaft, afulcrum memberconnected to said lever and having anormally fixed pivot, and

means for adjusting the axis of said pivot.

15. In a sewing machine, the combination of "needle mechanism, a looper,and means for imparting to said looper a four motion path of movementand including means adjustable for varying said movement to cause thelooper to move a greater distance forwardly and a' greaterdistancerearwardly. at the opposite ends of itstrans'verse movementinto-and out of the needle loops.: I

' a .16. The combination-of a drive shaft, a

looper shaft, a looper carried by said shaft, a reciprocating leverconnecting said shafts, a fulcrum member, for said lever, a shaftpivotally supporting said member, and means'for' angularly adjustingsaid shaft.

17 In a sewin machine, the combination" of a hollowYmac ine framecomprising an oil reservoir having walls enclosing the same against theescapeof oil, needle mechanism,

looper mechanism including a'looper, means for imparting to said loopera four motion' path of movement and including means adjustable forvarying said path tocause the looper to move a greater distanceforwardly and a greater distance rearwardly at the opposite ends of itstransverse movement mm and out of the needle loops, said last meansextending through a wall of said frame for access outside the frame.

18; In a sewing machine, the combination of a supporting shaft, acarrier having a central opening provided with a marginal circularflange, a looper comprising a blade offset. at its rear end. to providea shank 6X- tending rearwardly of the looper blade, said shank having acurved edge seated on said flange, and means for adjusting said looperon said flange.

19. In a sewing machine, the combinat on of a supporting shaft, acarrier compris ng a curved body having a central openlng and apair ofcircular marginal flanges projecting at opposite sides of the body, apair of loopers adjustably mounted on said flanges at opposite sides ofthe body, each looper comprising a blade and a shank, the shank havingthe bottom edge curved concentrically with said flange and seatedthereon.

20. In a. sewing machine, the combination of a supporting shaft, acarrier mounted on said shaft, a looper adjustably mounted on saidcarrier at one side of the shaft, and a needle guard adjustably mountedon said carrier at the opposite side of said shaft.

21,. In a sewing machine, the combination of a supporting shaft, acarrier mounted on said shaft, a looper mounted on the carrler at oneside of the shaft, a needle guard mounted on the carrier at the oppositeside of the shaft, and means for relatively adjusting said looper andneedle guard.

22. In a sewing machine, the combination ,of a supporting shaft, acarrier having a central opening provided with a marginal circularflange, a looper having a curved shank adjustably mounted on saidflange, and a needle guard having a curved shank adjnstably seated onsaid flange.

23. In a sewing machine, the combination of a looper shaft, a carriermounted on said shaft, a pair of loopers mounted at opposite sides ofsaid carrier and at one side of said shaft, and a pair of. needle guardsmounted at opposite sides of said carrier and at the other side of saidshaft, said loop-' ers and needle guards having each a shank providedwith an arcuate slot to permit adjustment relatively to said carrier.

24. As an article of manufacture, a loopor having an elongated bladeprovided with a pair of thread eyes, and a groove therebetween, saidgroove having an opening of less width than the groove.

25. As an article of manufacture, a looper having a curved bladeprovided with a pair of thread eyes, and a groove therebetween, saidgroove being closed at one side and having an opening of less width atthe opposite side.

26. As an article of manufacture, a looperhaving a blade provided with apair of thread eyes, a slot connecting said thread eyes, said slot beingwidened lengthwise thereof to provide a groove overlapped by alongitudinal edge of said slot.

27. As an article of manufacture, a needle guard comprising a holderportion, and bent wire formed guard adjustably connected thereto, saidholder portion also having a cur ed supporting portion having a curvedslot.

28. In a sewing machine, the combination of a machine frame, a hollowoil carrying work arm enclosed against the escape of oil, a hearing atthe front end of said arm, a looper shaft journaled in said bearing, andthread nipper mechanism in front of said bearing.

29. In a sewing machine, the combination of a hollow oil carrying workarm enclosed against the escape of oil to the outside, a looper shafttherein, a bearing for said shaft at the free end of the arm, threadcontrolling means at the free end of said arm and comprising actuatingmeans carried by the looper shaft in front of said bearing, and meansfor conducting thread thru said work arm to the thread controlling meanswhereby contact of the thread with the oil in the work arm is precluded.

80 In a sewing machine, the combination of a machine frame, a hollow oilcarrying work arm enclosed against the escape of oil to the outside, alooper shaft extending thru said arm, looper and thread nipper mechanismat the forward end of said arm, and means for conducting thread to saidmechanism and cooperating therewith to prevent contact of the threadwith the oil in said arm.

31. In asewing machine, the combination of an oil carrying hollow workarm, oil tight to preclude the escape of oil to the outside, looper andthread controlling means at the free end of said arm, uneans forconducting a flow of oil thru the arm, means for conducting thread thruthe arm to said thread controllingmeans and cooperating with said lastmeans to preclude contact of the thread with the oil. 7

32. In a sewing machine, the combination of a hollow work arm carryingan oil bath and enc osed against the escape of oil to the outside,thread handling mechanism and thread guilding mechanism within said workarm, and means for precluding contact of the oil with the thread withinsaid arm.

33. In a sewing machine, the combination of a hollow machine arm, alooper shaft located therein, a looper, a thread take-up member, andmeans for moimting said looper andmember on said shaft and accessible atthe freeend of said arm.

34:. In a sewing machine, the combination of a hollow machine arm, alooper shaft therein, a thread take-up member and a looper carried bysaid looper shaft in front of said bearing andaccessible from the freeend of said arm.

36. In a sewing machine, the combination of a hollow Work arm, aloopershaft extending t-herethrough, albearing for said looper shaft mountedat the free end of said arm, thread nipper mechanism extending betweensaid bearing and the wall of the work arm, and operating means for said'mechanism accessible from the free end of the work arm. v

37. In a sewing machine, the combina- 'tion of a hollow work arm, alooper shaft therein, a bearing for said shaft at the free end of thearm, and thread controlling means accessible from the free end of, saidarm, andcomprising a cam carried by said looper shaft in front of saidbearing.

38. In a sewing machine, the combination of a hollow work arm, a loopershaft,

a detachable end cap for said arm,\a looper,

a thread take-up and a thread nipper all housed within said end cap, andmeans also housed within said cap and carried by the looperishaftfonoperating said nipper.

39. In a sewing machine, the combination of a hollow supporting member,stitch ing mechanism, looper mechanism, supported in said supportingmember and in. cluding a looper shaft, a cam carried by. said shaft, atwo-arm rocklever located adjacent to the free end of saidsupportingmember, one arm having a cam surface engaged by said cam, and a threadclamp supported by the other arm. Y

40. In a sewing machine,"the combination of a hollowsupporting member,stitching mechanism, looper mechanism sup-v ported in said supportingmember and including a looper shaft, a cam carried by said shaft, atwoarm rock lever carried by said supporting member, one arm having acam surface engaged by said cam, and a thread clamp carried by the otherarm, said cam having a four-motion path of movement for rocking saidlever.

41. In a sewing machine, the combination of a hollow work arm, a loopershaft, a cam carried thereby,-a swinging lever engaged by said cam, anda thread nipper shiftably carried by said lever and operated thereby.

42. In a sewing machine, the combina tion of a hollow oil carrying workarm enclosed against theescape of oil to the outside, means forconducting a flow of oil thru the work arm, and thread control meanslocated within said workarm for handling the thread atthe free end ofthe arm to pre-' clude contact of the thread with the oil in said arm.

43. In a sewing machine, the combination of a hollow work arm, a loopershaft, a bearing for said shaft at the free end of the arm, a rock leverpivotedto said bearing, thread nipper .means extending be- I tween saidbearing and thewallof the arm and carried by said lever, and a camcarried by said looper shaft for rocking said lever.

,44. In a sewing machine, the combination of a drive shaft, a hollowsupporting member, looper mechanism supported therein and comprising alooper shaft, a cam earned by I said shaft, thread controllingmeansoperated by said cam, and means for impartinga four motion movement tosaid cam thereby to operate said thread controllingmeans.

.45. In a sewing machine, the combination of a hollow work arm, a loopershaft extending therethrough, a bearingat the free end of the arm forsaid looper shaft, a

looper carried bysaid shaft and a thread controlling member carried bythe looper shaft between said looper and bearing and accessible from thefree end of said arm.

tion of a tubular work support, an end cap detacha'bly mounted at thefreeend thereof,

a looper shaft, a looper and a thread take-up carried by said shaft, andhoused within said end cap and accessible upon detaching said cap.

47 In a sewing machine, the combination of a looper shaft,,a swingingthread guide, a thread clamp carried thereby, said guide having anextended arm, and a cam' -OELIIl6d by sald shaft and engageable withsaid arm for swinging the same.

u 46. In a sewing machine, the combma- 48. In a sewing machine, thecombination of a hollow work arm, a swinging thread guide locatedtherein, means for pivotally supporting said guide to permit the same toswing toward and from the wall of the Work arm, a thread clamp pivotedto said guide and cooperating with the wall of the work arm, and meansfor swinging said guide from the looper shaft.

49. In a sewing machine, the combination of a hollow work arm, loopermechanism comprising a looper shaft extending therethrough, a loopercarried bysaid shaft, a rear bearing for said looper shaft detachablyconnected to the work arm, a front bearing for the looper shaftdetachably connected to the work arm, said bearings being detachable topermit the looper mechanism and said bearings to be shifted togetherinto or out ofthe arm. I

Signed at Nyack, New York, this 8th day of October, 1923.

JOHN P. WEIS.

